1. Field of the Invention
The present invention relates to a magnetic tape apparatus, and more particularly, to a magnetic head cleaner mechanism for cleaning a magnetic head of a magnetic tape apparatus.
2. Description of the Related Art
Conventionally, a magnetic tape apparatus is known which has a magnetic head cleaner mechanism for purposes of cleaning a magnetic head thereof without troubling an operator about such work. As a prior art example, a magnetic tape apparatus described in Laid-open Japanese Patent Application No. 328635/1999 will be described below with reference to FIGS. 1 through 3. FIG. 1 is a schematic diagram illustrating the configuration of the magnetic tape apparatus. FIGS. 2, 3 are enlarged views of a magnetic head cleaner mechanism equipped in the magnetic tape apparatus, wherein FIG. 2 shows that brush 103 is in contact with a magnetic head 101, and FIG. 3 shows that brush 103 is spaced apart from magnetic head 101.
As illustrated in FIG. 1, the magnetic tape apparatus comprises magnetic head 101 for writing data into magnetic tape 102 and reading data recorded on magnetic tape 102; and machine reel 106 rotatable by a rotary mechanism, not shown. The magnetic tape apparatus is loaded with cartridge 104 which can wind up magnetic tape 102 and hold wound magnetic tape 102 therein. Generally, cartridge 104 is loaded into the magnetic tape apparatus, with magnetic tape 102 wound up and held in cartridge 104. At that time, leader block 105 attached to a leading end of magnetic tape 102 is latched on the case of cartridge 104. The magnetic tape apparatus also has threader arm 116 which comprises thread pin 107 disposed at a leading end thereof for engagement with leader block 105, and is driven by a driving mechanism, not shown, to move thread pin 107 along predetermined trajectory 107a. 
As cartridge 104 is loaded into the magnetic tape apparatus for recording or reproducing magnetic tape 102, thread pin 107 is brought into engagement with leader block 105 positioned at an end of the case of cartridge 104. Then, thread pin 107 is moved, together with leader block 105, along trajectory 107a to the center of machine reel 106 passing by magnetic head 101. When machine reel 106 is rotated in this state, magnetic tape 102 can be wound around machine reel 106. Thus, recording or reproduction can be performed on magnetic tape 102 while the magnetic tape 102 is being fed by being wound around machine reel 106.
The foregoing magnetic tape apparatus has a magnetic head cleaner mechanism with brush 103 which is brought into contact with magnetic head 101 for cleaning the same. The magnetic head cleaner mechanism comprises rotatably supported opening link 110; closing link 111; and follower link 120. Follower link 120 has an elongated hole formed through a leading end thereof, and opening link 110 has a leading end engaged with and slidable along the elongated hole of follower link 120. Brush 103 is disposed near the location at which opening link 110 is engaged with follower link 120. Closing link 111 is engaged with opening link 110 such that it is rotated together with closing link 111.
As illustrated in FIG. 2, follower link 120 includes click tab 121a which is in contact with click spring 121b. A clicking mechanism comprised of click tab 121a and click spring 121b allows follower link 120 to stay at two predetermined positions, i.e., a position at which brush 103 comes into contact with magnetic head 101 as illustrated in FIG. 2, and at a position at which brush 103 moves away from magnetic head 101 as illustrated in FIG. 3.
When neither recording nor reproduction is performed, the magnetic head cleaner mechanism remains with brush 103 in contact with magnetic head 101, as illustrated in FIG. 2. In this state, magnetic head 101 can be cleaned by vibrating magnetic head 101 in a vertical direction to a track direction (vertical direction on the drawing sheet).
In the state illustrated in FIG. 2, a portion of opening link 110 lies on trajectory 107a of thread pin 107. Therefore, upon recording or reproduction, after cartridge 104 is loaded, as thread pin 107 carrying leader block 105 is moved along trajectory 107a, opening link 110 is pushed by thread pin 107. This causes transition of the magnetic head cleaner mechanism to the state illustrated in FIG. 3, where brush 103 is away from magnetic head 101.
In the state illustrated in FIG. 3, a portion of closing link 111 lies on trajectory 107a of thread pin 107. Therefore, after completion of recording or reproduction, as thread pin 107 carrying leader block 105 is moved along trajectory 107a, closing link 111 is pushed by thread pin 107. This causes the magnetic head cleaner mechanism to return again to the state illustrated in FIG. 2.
The prior art example described above has the following disadvantages. First, since the magnetic head cleaner mechanism and the threading mechanism are independent of each other, a larger number of parts are required for the magnetic head cleaner mechanism, resulting in an increase in the unit price of the mechanism. Also, for switching the brush to come into contact with the magnetic head and move away from the same, the threader pin must be operated over a wide range. Further, while the clicking mechanism is used for fixing the brush at the predetermined positions, this clicking mechanism may likely cause a transition of the brush between the state illustrated in FIG. 2 and the state illustrated in FIG. 3 due to vibrations or the like. Such a transition could cause brush 103 to collide with head 101, for example, during recording or reproduction. Moreover, since opening link 110, closing link 111 and follower link 120 are moved over a large distance, the magnetic head cleaner mechanism requires a large space.
It is an object of the present invention to provide a magnetic head cleaner mechanism comprised of a smaller number of parts, as compared with the prior art example, which is reliably capable of cleaning a magnetic head without fail even at a low accuracy of parts.
It is another object of the present invention to provide a magnetic head cleaner mechanism which does not require an extra space.
It is a further object of the present invention to provide a magnetic head cleaner mechanism which is free from defective operations even with vibrations applied thereto.
A magnetic tape apparatus, which incorporates the magnetic head cleaner mechanism of the present invention, is loaded with a cartridge which can wind up a magnetic tape and hold the wound magnetic tape therein. The magnetic tape apparatus has a magnetic head, a machine reel, and a threader arm. The threader arm holds a leading end of a magnetic tape held in the cartridge, and leads it from the cartridge to the machine reel and vice versa passing by the magnetic head. After the leading end of the magnetic tape has been led to the machine reel, the machine reel is rotated to wind the magnetic tape therearound, so that the magnetic tape is fed passing by the magnetic head. In this event, the magnetic head writes data onto the magnetic tape or reads data written on the magnetic tape.
The magnetic head cleaner mechanism of the present invention is provided for cleaning the magnetic head in the magnetic tape apparatus as described above. The magnetic head cleaner mechanism has a brush arm. The brush arm has a first portion rotatably attached to the threader arm, and a second portion slidably engaged with a cam groove. A brush holder for holding a brush is attached to the brush arm.
In the foregoing configuration, the brush arm moves following movements of the threader arm for moving the leading end of the magnetic tape between the cartridge and the machine reel. The movement of the brush arm in this event can be adjusted by controlling the pattern of the cam groove, the position at which the brush arm is attached to the threader arm, and so on. Thus, the magnetic head cleaner can be configured such that the brush comes into contact with the magnetic head when the threader arm stays at a predetermined position and moves away from the magnetic head when the threader arm leaves that position.
In this way, the magnetic head can be cleaned by the brush which is brought into contact with the magnetic head without fail when the threader arm is forced to the predetermined position. On the other hand, except when the magnetic head is cleaned, the threader arm is moved away from the predetermined position, thereby making it possible to keep the brush away from the magnetic head without fail and securely maintain the brush away from the magnetic tape. By thus keeping the brush from the magnetic head except when the magnetic head is cleaned, it is possible to delay a deterioration of the brush and extend the lifetime of the magnetic head cleaner mechanism.
The foregoing configuration comprises the magnetic head cleaner mechanism using the threader arm constituting the threading mechanism as one component of the magnetic head cleaner mechanism, thereby making it possible to reduce the number of components required for the magnetic head cleaner mechanism and hence save the cost.
The cam groove which forms part of the magnetic head cleaner mechanism can be disposed beside the magnetic head, without the need for disposing it in front of the magnetic head, so that a large space need not be ensured in front of the magnetic head for installing the magnetic head cleaner mechanism. For this reason, the magnetic tape apparatus which incorporates the magnetic head cleaner mechanism according to the present invention can be made in a size equal to a conventional magnetic tape apparatus. Therefore, the magnetic tape apparatus which comprises the improved magnetic head cleaner mechanism according to the present invention can be installed in a system which has a slot in determined dimensions for incorporating a magnetic tape apparatus therein.
In the foregoing configuration, the predetermined position of the threader arm at which the brush comes into contact with the magnetic head may be the position at which the end of the magnetic tape is pulled out from the cartridge.
In addition, a resilient element such as a leaf spring may be provided for urging the brush holder toward the magnetic head when the threader arm stays at the predetermined position. This can ensure that the brush comes into contact with the magnetic head when the threader arm is moved to the predetermined position. Also, in this case, since the brush can be brought into contact with the magnetic head without fail even if associated parts exhibit a slightly low accuracy, the manufacturing cost can be reduced by degrading the accuracy of parts without damaging the performance of the magnetic head cleaner mechanism.
The cam groove which forms part of the magnetic head cleaner mechanism may be formed in a brush cam plate attached to a deck base on which associated members of the magnetic tape apparatus are fixed, or formed directly in the deck base.
Movements of the brush associated with movements of the threader arm can be set as appropriate in accordance with the pattern of the cam groove. The cam groove can be shaped such that the brush is moved not only in a direction parallel to the surface of the magnetic head but also in a direction perpendicular to the surface of the magnetic head. In this way, the brush can be promptly moved away from the magnetic head when the threader arm is moved from the aforementioned predetermined position.
The above and other objects, features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings which illustrate examples of the present invention.